Environmental and evolutionary controls in animal-sediment interactions at the onset of the Cambrian explosion.

The Cambrian explosion was a time of groundbreaking ecological shifts related to the establishment of the Phanerozoic biosphere. Trace fossils, which are the products of animals interacting with their substrates, provide a key record of the diversification of the benthos and the evolution of behavioral complexity through this interval. The Chapel Island Formation of Newfoundland in Canada hosts the most extensive trace-fossil record from the latest Ediacaran to Cambrian Age 2, spanning about 20 million years continuously.

The Invasion of the Land in Deep Time: Integrating Paleozoic Records of Paleobiology, Ichnology, Sedimentology, and Geomorphology.

The invasion of the land was a complex, protracted process, punctuated by mass extinctions, that involved multiple routes from marine environments. We integrate paleobiology, ichnology, sedimentology, and geomorphology to reconstruct Paleozoic terrestrialization. Cambrian landscapes were dominated by laterally mobile rivers with unstable banks in the absence of significant vegetation.

Quantifying ecospace utilization and ecosystem engineering during the early Phanerozoic-The role of bioturbation and bioerosion.

The Cambrian explosion (CE) and the great Ordovician biodiversification event (GOBE) are the two most important radiations in Paleozoic oceans. We quantify the role of bioturbation and bioerosion in ecospace utilization and ecosystem engineering using information from 1367 stratigraphic units. An increase in all diversity metrics is demonstrated for the Ediacaran-Cambrian transition, followed by a decrease in most values during the middle to late Cambrian, and by a more modest increase during the Ordovician.

A new insect trackway from the Upper Jurassic-Lower Cretaceous eolian sandstones of São Paulo State, Brazil: implications for reconstructing desert paleoecology.

The new ichnospecies isp. nov. is described from the Upper Jurassic-Lower Cretaceous Botucatu Formation of Brazil.

Palaeoecological implications of the preservation potential of soft-bodied organisms in sediment-density flows: testing turbulent waters.

Interpreting how far organisms within fossil assemblages may have been transported and if they all originated from the same location is fundamental to understanding whether they represent true palaeocommunities. In a three-factorial experimental design, we used an annular flume to generate actualistic sandy sediment-density flows that were fast (2 ms) and fully turbulent in order to test the effects of flow duration, sediment concentration, and grain angularity on the states of bodily damage experienced by the freshly euthanized polychaete . Results identified statistically significant effects of flow duration and grain angularity.

Skimming the surface with Burgess Shale arthropod locomotion.

The first arthropod trackways are described from the Middle Cambrian Burgess Shale Formation of Canada. Trace fossils, including trackways, provide a rich source of biological and ecological information, including direct evidence of behaviour not commonly available from body fossils alone. The discovery of large arthropod trackways is unique for Burgess Shale-type deposits.

Morphogenesis of an extended phenotype: four-dimensional ant nest architecture.

Animals produce a variety of structures to modify their environments adaptively. Such structures represent extended phenotypes whose development is rarely studied. To begin to rectify this, we used micro-computed tomography (CT) scanning and time-series experiments to obtain the first high-resolution dataset on the four-dimensional growth of ant nests.